A large number of SEMs, AFMs and the like are used to locally evaluate, for example, nanodots formed on a surface and nanofabrication of a semiconductor device. On the other hand, as a complementary method of performing measurements on an average structure, grazing-incidence small-angle X-ray scattering (GISAXS), in which X-rays are irradiated to a surface at a grazing angle, the intensity of the X-ray scattering is analyzed and thus measurements are performed on the nanostructure of the surface, has been widely used in recent years because a powerful synchrotron source has been realized.
As a technology on such small-angle scattering, there is one (for example, see patent document 1) that achieves high resolution by forming the focal point of X-rays on a detector with an optical element. A two-dimensional small-angle X-ray camera disclosed in patent document 1 forms a well-defined two-dimensional beam by a combination of a small focus source and a two-dimensional multilayer optical element.
As a similar technology, there is disclosed a technology that uses a Kirkpatrick-Baez scheme to focus, with two mirrors, X-rays in the vicinity of a detector (for example see non-patent document 1). In non-patent document 1, there is also disclosed an optical system that arranges two mirrors side by side to focus X-rays.
On the other hand, with respect to small-angle scattering, a technology for forming the focal point of X-rays onto a sample is also disclosed (for example, see patent document 2). The device disclosed in patent document 2 converges X-rays in a horizontal direction with a first mirror, converges X-rays in a vertical direction with a second mirror, and focuses the X-rays to a 0.1 mm by 0.1 mm region on the sample.